ADF Gauge with "Beam"?

[Jorge]

All,

I posted a thread over at FSDeveloper and have had a few nibbles, but was wondering if anyone had any input here.

I'm trying to get a simple ADF gauge that has a light which lights up when the needle for ADF 1 and the set bearing on the card are equal. This would, in theory, allow for a "beam" type track to the station. In other words, no match between the two and the light would go out. Back where they match, and the light comes back on.  You also have ADF 2 for next station reference, so when you are within range of that one you dial it in and dial the card to the course you want to the station.

Think of it as a "poor pilot's" LFRR set.

Any idea how this would be done? Here's what I have so far using freeware alphasim gauges as a basis:


==================================================================

<Gauge Name="pw rr v1" Version="1.0" Author="Jorge L. Rechani">

<!-- Based on original work by Herbert Pralle -->
<!-- of Alphasim. Freeware ADF and VOR radio -->
<!-- by said author of Alphasim were original -->
<!-- gauges this is based on. -->

<Image Name="ADF_backgrnd.bmp"/>

<!-- ADF card with direction numbers -->

<Element>
<Position X="86" Y="86"/>
<Image Name="ADF_card.bmp" Luminous="1">
<Axis X="72" Y="72"/>
</Image>
<Rotate>
<Value>(A:ADF CARD,radians) 3 *</Value>
</Rotate>
</Element>

<!-- ADF1 Needle -->

<Element>
<Position X="86" Y="86"/>
<Image Name="ADF_Needle_01.bmp" Luminous="1">
<Axis X="55" Y="5" PointsTo="East"/>
</Image>
<Rotate>
<Value>(A:ADF SIGNAL:1, number) abs 10 > if{ (A:ADF RADIAL:1,radians) pi 2 / - } els{ 0 }</Value>
<Failures>
<GAUGE_GYRO_HEADING Action="Freeze"/>
<SYSTEM_ELECTRICAL_PANELS Action="0"/>
<GAUGE_ADF Action="Freeze"/>
<SYSTEM_ELECTRICAL_AVIONICS Action="0"/>
</Failures>
<Delay DegreesPerSecond="180"/>
</Rotate>
</Element>

<!-- ADF2 Needle -->

<Element>
<Position X="86" Y="86"/>
<Image Name="ADF_Needle_02.bmp" Luminous="1">
<Axis X="55" Y="5" PointsTo="East"/>
</Image>
<Rotate>
<Value>(A:ADF SIGNAL:2, number) abs 10 > if{ (A:ADF RADIAL:2,radians) pi 2 / - } els{ 0 }</Value>
<Failures>
<GAUGE_GYRO_HEADING Action="Freeze"/>
<SYSTEM_ELECTRICAL_PANELS Action="0"/>
<GAUGE_ADF Action="Freeze"/>
<SYSTEM_ELECTRICAL_AVIONICS Action="0"/>
</Failures>
<Delay DegreesPerSecond="180"/>
</Rotate>
</Element>

<!-- Flags in case of failures, no signal, etc. -->

<Element>
<Position X="52" Y="57"/>
<Select>
<Value>(A:CIRCUIT GENERAL PANEL ON,bool) (A:Avionics master switch,bool) && (A:ADF SIGNAL:1, number) 10 > &&</Value>
<Case Value="0">
<Image Name="ADF_flag.bmp" Luminous="1">
<Axis X="0" Y="0"/>
</Image>
</Case>
</Select>
</Element>

<Element>
<Position X="100" Y="57"/>
<Select>
<Value>(A:CIRCUIT GENERAL PANEL ON,bool) (A:Avionics master switch,bool) && (A:ADF SIGNAL:2, number) 10 > &&</Value>
<Case Value="0">
<Image Name="ADF_flag.bmp" Luminous="1">
<Axis X="0" Y="0"/>
</Image>
</Case>
</Select>
</Element>

<!-- ADF Masking Cover -->

<Element>
<Position X="0" Y="0"/>
<Image Name="ADF_cover.bmp" Luminous="1"/>
</Element>

<!-- Knob to change the ADF Card / OBS Heading -->

<Element>
<Position X="153" Y="153"/>
<Image Name="ADF_Radio_knob1.bmp">
<Axis X="17" Y="17"/>
</Image>
<Rotate>
<Value>(A:ADF CARD,radians) 3 *</Value>
</Rotate>
</Element>

<!-- Course Lamp -->

<!-- If the Card setting is equal to the radial, -->
<!-- the lamp should come on. -->

<Element>
<Position X="0" Y="141"/>
<Image Name="Course_Lamp_bg.bmp"/>
<Select>
<Value>{ (A:ADF RADIAL:1,radians) pi 2 / - } {(A:ADF CARD,radians) 3 *} == </Value>
<Case Value="1">
<Image Name="Course_Lamp.bmp" Luminous="1">
<Axis X="0" Y="0"/>
</Image>
</Case>
<Case Value="0">
<Image Name="Course_Lamp_bg.bmp" Luminous="1">
<Axis X="0" Y="0"/>
</Image>
</Case>
</Select>
</Element>

<!-- To make sure no negative results for NAV radials -->

<!-- (A:NAV2 RADIAL, degrees) 0 < -->
<!-- if{ 360 (A:NAV2 RADIAL, degrees) + (>L:VOR2 Radial, degrees) } -->
<!-- els{ (A:NAV2 RADIAL, degrees) (>L:VOR2 Radial, degrees) } -->

<!-- Mouse to turn OBS and Card -->

<Mouse>
<Area Left="136" Right="170" Top="136" Bottom="170">
<Area Right="25">
<Click Event="ADF_CARD_DEC" Repeat="Yes"/>
</Area>
<Area Left="25">
<Cursor Type="UpArrow"/>
<Click Event="ADF_CARD_INC" Repeat="Yes"/>
</Area>
</Area>
</Mouse>

<!-- Course Display -->

<Element>
<Position X="95" Y="95"/>
<Text X="28" Y="10" Bright="Yes" Length="3" Font="Arial" Color="antiquewhite" Adjust="Center" VerticalAdjust="Center">
<String>%((A:ADF CARD, degrees))%!03d!</String>
</Text>
</Element>

</Gauge>

==================================================================

Thanks for any input!

Regards,

Jorge
Miami, FL

[Tom/CalClassic]

Hi,

In my hands (A:ADF RADIAL:1,radians) pi 2 / - is never equal to (A:ADF CARD,radians) 3 *, and thus the light could never come on.

(A:ADF RADIAL:1,radians) pi 2 / - varies between -2 and -8 while spinning the plane around.

(A:ADF CARD,radians) 3 * varies between 0 and 19 as I spin the ADF card around.

Thus they could never be equal.

Also, since you are requiring them to be exactly equal, the light will almost never come on, since you have to be within a tiny fraction of a degree for the light to come on.

Hope this helps,

[Jorge]

Tom,

Thanks for the heads up on that. I figured something was amiss, but since I'm still new at this I'm banging my head against the wall. I changed the code so far to read: <Value>(A:ADF RADIAL:1,degrees) (A:ADF CARD,degrees) == </Value> with no change to: <String>%((A:ADF CARD, degrees))%!03d!</String> and still nothing. I did make the numbers a bit bigger with a "Y" size of 18. I appreaciate you looking at it. I'll have to see what I can find regarding the reason even the "degrees" are different an all three. I thought with the same unit on all three they should at least be the same?

Regards,

Jorge

[ddawson]

As Tom points out, you're dealing with floating point numbers here.
The chances of the two values being exactly equal may be very small. (0.999999998 is not equal to 1.0)
You're better off subtracting one value from the other, making the result absolute, and then checking to see if the difference is small enough that you can consider it to be zero.

Doug

[Jorge]

Gentlemen,

Thanks for the input. I'll definately be looking at those. I was thinking of maybe making the "degrees" input absolute or maybe normalized into a non-floating number?

Jorge

[Tom/CalClassic]

As I understand it you want the ADF to work like the one on the DC-3, right? A manually operated card with two needles, NDB1 and NDB2? And when do you want the light to come on? Let's say the plane is heading 180 degrees (S), and the NDB is at 90 degrees (E). Do you want the light to come on:

1. When the E on the card is aligned with the needle (i.e. you are traveling south, not towards the NDB)? That would be when the card heading (E) matched the NDB heading (E). That doesn't sound like a beam to me?

2. The needle points straight ahead (i.e. you are heading towards the NDB) and the card matches your heading, then you are just flying to the NDB, not on a specific heading.

3. But if you require for the light to come on:

a. Needle matches plane's heading
b. Card is set to beam heading
c. Card matches plane's heading

Then you are flying on a specific heading towards the NDB, which could simulate a "beam". But how you would specify the beam for every NDB in the world is a big task, one that took a lot of work for the RR folks.

So I assume you want #2, and you can set the card heading yourself according to charts or by random selection?

[Jorge]

All,

Thanks for the information. I've tried several things from reading forums and tutorials and still nothing. I did manage at one point to have the light come on when the card read a specific number, but that's not what I was after. My inspiration came from the FS9 Vega, but I'll continue with that below. In short, this is what I was looking for:

1. Set the card to any number you want to use as a "track" to the NDB.
2. Fly the aircraft (or have it on the ground if you can receive the station signal) until the bearing to the station is the same as what you dialed into the card.
3. Light should stay on when both numbers match or are within a range you specify in the code (plus or minus one degree, for example).

Back to my inspiration from the Vega: I can't even get the default FS9 Vega ADF to work either. I figured that gauge was about as close to what I was trying to do as possible. I decompressed the cab file to a folder, then edited the xml file with Notepad++ to remove the 360 + section as stated online by Tom and others, then saved the xml file in the same location. When I loaded the Vega afterwards I still had nothing. The needle was still pegged to the right and the tooltip readout was also way off from anything that would make sense, just like before. I exited FSX:SE and restarted only to find the same thing happening.

I'm starting to wonder if there is something wrong with the FSX:SE edition of FSX since most folks with the updated Vega gauge can get it to work after the edit. I was going to test my light with that gauge if I could get it to work, specifically it would light up when the value of the needle was between -1 and 1 (i.e. anything close to "0" on the needle). Since I'm not able to even get a default gauge to work as it should - even after doing the changes to the xml file as posted - I'm wondering if it has something to do with FSX:SE.

Any ideas?

Regards,

Jorge
Miami, FL

[Tom/CalClassic]

I guess I still don't understand. Just because the bearing to the station matches the number on the card does *not* mean that you would be flying towards the station - you could be flying at 90 degrees to it and fly right by it. See my previous post explaining this (choice #1). Having the light come on will fly you into a mountain...

The Vega gauge is not pegged when the bearing to the station is less then 10 degrees either way. This has nothing to do with a rotating card.

It sounds to me like you want the light to come on when:

1. Set the card to any number you want to use as a "track" to the NDB.
2. Fly the aircraft (or have it on the ground if you can receive the station signal) until the bearing to the station is the same as what you dialed into the card AND THE PLANE IS FLYING THE CARD HEADING.
3. Light should stay on when both numbers match or are within a range you specify in the code (plus or minus one degree, for example).

Right?

[Tom/CalClassic]

Here is a test gauge that does what I think you want. If you back up your ADF.xml gauge in the Gauges/Z_DC6KMTG folder and create a new xml file with that name using this code, then the DC-6 panel will display this gauge. It has a lot of debug numbers displaying, but you should see a green light come on at the left edge of the gauge when you are lined up with the station and the card is set to that heading. Hope this helps.

<Gauge Name="pw rr v1" Version="1.0" Author="Jorge L. Rechani">

<!-- Based on original work by Herbert Pralle -->
<!-- of Alphasim. Freeware ADF and VOR radio -->
<!-- by said author of Alphasim were original -->
<!-- gauges this is based on. -->

<Image Name="RMI_BACK.bmp" ImageSizes="256,256"/>

<!-- ADF card with direction numbers -->


<Element>
       <Position X="128" Y="128"/>
       <Image Name="RMI_ROSE.bmp" ImageSizes="226,226" UseTransparency="Yes">
                 <Axis X="113" Y="113"/>
</Image>
<Rotate>
<Value>(A:ADF CARD,radians) </Value>
</Rotate>
</Element>

<!-- ADF1 Needle -->

<Element>
              <Position X="128" Y="128"/>
                   <Image Name="RMI_NAV1_ND.bmp" ImageSizes="33,207">
                       <Axis X="16.5" Y="103.5"/>
</Image>
<Rotate>
<Value>(A:ADF SIGNAL:1, number) abs 10 > if{ (A:ADF RADIAL:1,radians) } els{ 0 } </Value>
<Failures>
<GAUGE_GYRO_HEADING Action="Freeze"/>
<SYSTEM_ELECTRICAL_PANELS Action="0"/>
<GAUGE_ADF Action="Freeze"/>
<SYSTEM_ELECTRICAL_AVIONICS Action="0"/>
</Failures>
<Delay DegreesPerSecond="180"/>
</Rotate>
</Element>

<!-- ADF2 Needle -->

<Element>
              <Position X="128" Y="128"/>
              <Image Name="RMI_NAV2_ND.bmp" ImageSizes="33,207">
                 <Axis X="16.5" Y="103.5"/>
</Image>
<Rotate>
<Value>(A:ADF SIGNAL:2, number) abs 10 > if{ (A:ADF RADIAL:2,radians) } els{ 0 } </Value>
<Failures>
<GAUGE_GYRO_HEADING Action="Freeze"/>
<SYSTEM_ELECTRICAL_PANELS Action="0"/>
<GAUGE_ADF Action="Freeze"/>
<SYSTEM_ELECTRICAL_AVIONICS Action="0"/>
</Failures>
<Delay DegreesPerSecond="180"/>
</Rotate>
</Element>

<!-- Flags in case of failures, no signal, etc. -->

<Element>
<Position X="52" Y="57"/>
<Select>
<Value>(A:CIRCUIT GENERAL PANEL ON,bool) (A:Avionics master switch,bool) and (A:ADF SIGNAL:1, number) 10 > and </Value>
<Case Value="0">
<Image Name="ADF_flag.bmp" Luminous="1">
<Axis X="0" Y="0"/>
</Image>
</Case>
</Select>
</Element>

<Element>
<Position X="100" Y="57"/>
<Select>
<Value>(A:CIRCUIT GENERAL PANEL ON,bool) (A:Avionics master switch,bool) and (A:ADF SIGNAL:2, number) 10 > and </Value>
<Case Value="0">
<Image Name="ADF_flag.bmp" Luminous="1">
<Axis X="0" Y="0"/>
</Image>
</Case>
</Select>
</Element>

<!-- ADF Masking Cover -->

<Element>
<Position X="0" Y="0"/>
<Image Name="ADF_cover.bmp" Luminous="1"/>
</Element>

<!-- Knob to change the ADF Card / OBS Heading -->

<Element>
<Position X="220" Y="220"/>
<Image Name="OBS_Knob.bmp">
        <Axis X="25" Y="25"/>
</Image>
<Rotate>
<Value>(A:ADF CARD,radians) 3 *</Value>
</Rotate>
</Element>

<!-- Course Lamp -->

<!-- If the Card setting is equal to the radial, -->
<!-- the lamp should come on. -->

<Element>
<Position X="0" Y="141"/>
<Image Name="Course_Lamp_bg.bmp"/>
<Select>
<Value> (A:ADF RADIAL:1,degrees) 360 + abs 10 < (A:Plane heading degrees Magnetic, radians) (A:ADF CARD,radians) - abs 0.1 < and </Value>
<Case Value="1">
<Image Name="IDENT_LIGHT.bmp" Luminous="1">
<Axis X="0" Y="0"/>
</Image>
</Case>
<Case Value="0">
<Image Name="Course_Lamp_bg.bmp" Luminous="1">
<Axis X="0" Y="0"/>
</Image>
</Case>
</Select>
</Element>

<!-- Course Display -->

<Element>
<Position X="95" Y="95"/>
<Text X="200" Y="80" Bright="Yes" Length="30" Font="Arial" Color="antiquewhite" Adjust="Center" VerticalAdjust="Center">
<String>%((A:ADF CARD, degrees))%!03d!</String>
</Text>
</Element>

<!-- test printing-->
<Element>
<Position X="5" Y="5"/>
<Text X="900" Y="44" Bright="Yes" Length="400" Font="Arial" Color="#FFFFFF" Adjust="Left" VerticalAdjust="Center" Multiline="No" Fixed="No">
<String> %( (A:ADF RADIAL:1,degrees) 360 + abs  )%!3.2f! %( (A:ADF RADIAL:1,radians) (A:ADF CARD,radians) - )%!3.2f! %( (A:Plane heading degrees Magnetic, radians) )%!3.2f! %( (A:ADF CARD,radians) )%!3.2f!  %( (A:AUTOPILOT HEADING LOCK DIR, degrees) )%!3.2f! </String>
</Text>
</Element> <!-- test printing-->

<!-- To make sure no negative results for NAV radials -->

<!-- (A:NAV2 RADIAL, degrees) 0 < -->
<!-- if{ 360 (A:NAV2 RADIAL, degrees) + (>L:VOR2 Radial, degrees) } -->
<!-- els{ (A:NAV2 RADIAL, degrees) (>L:VOR2 Radial, degrees) } -->

<!-- Mouse to turn OBS and Card -->

<Mouse>
        <Tooltip>%((A:ADF CARD, degrees))</Tooltip>
        <Area Left="195" Right="245" Top="136" Bottom="255">
<Area Right="25">
<Cursor Type="DownArrow"/>
<Click Event="ADF_CARD_DEC" Repeat="Yes"/>
</Area>
<Area Left="25">
<Cursor Type="UpArrow"/>
<Click Event="ADF_CARD_INC" Repeat="Yes"/>
</Area>
</Area>
</Mouse>

</Gauge>

[Tom/CalClassic]

PS. This is based on your original code, so you should be able to copy the relevant parts from my code and paste it into yours. The only changes may be if your needles and rotating card point different directions than mine, etc.

[Jorge]

Thank You Tom!

I'll test it out as soon as I'm back home!

I'm glad I could finally explain myself (sort of) to the point where someone understood what I was trying to do. Not the best solution for the LFRR, but it can at least get you in the right direction for now with a stopgap gauge. I was completely missing the aircraft heading portion! My original flight instructor would hang me for that! ;-) That's what happens when you're slaved to an FMS at work for so many years!

Again, thank you for everything and as soon as I'm back home and on my rig I'll see if I can reproduce the results you got.

Regards,

Jorge
Miami, FL